Italian team Luna Rossa have threatened to pull out of the 2017 America's Cup over proposed changes to boat sizes.
America's Cup organisers plan to change the 62-foot catamarans to 45-footers to cut costs for the teams as the race has struggled to gain sponsorship.
Luna Rossa 62ft boat is already being built and the team said it is "distinctly opposed to the proposal".
Team New Zealand's involvement in the 35th staging of the race, in Bermuda, is in doubt after opposing the changes.
The Italians said they had not agreed to the rule change and that it needed the unanimous approval of all teams before such a decision could be made.
The team stated: "If the principle of unanimity of all challengers required to change the Class Rule were not to be respected Luna Rossa will be obliged to withdraw."
Great Britain's Ben Ainslie is due to take part in the event with his team BAR.
Ainslie helped Oracle Team USA to win the America's Cup in 2013.